The present invention relates to a method and apparatus for producing bags and, more particularly for producing continuous bags of thin material wherein each of the bags has an opening on a side.
Method and apparatus for the production of continuous bags of thin material, such as polyethylene is well known. One well known example of such bags is a common-day plastic bag which is used in grocery stores or supermarkets. These bags are characterized by being in a continuous roll on a reel with perforations through the bag separating one bag from the other. To use each bag, the shopper grasps a bag, tugs the bag, tearing it from the reel along the line of perforation. The bag then has an opening along the line of perforation. The line of perforation serves as the connection between one bag and another while on the reel, at the same time, once each bag is torn along the line of perforation, the line of perforation (line of tear) becomes the opening to the bag.
In certain applications, however, it is desirable to manufacture such continuous bags, with each bag connected to the adjacent bag and with each bag having an opening along one side of the perforation, or a line of tear along one side of the bag. Such continuous bags are used in other manufacturing processes in which items are inserted into each bag through the opening in a continuous fashion. Thus, in such application, it is desired to manufacture continuous bags of thin material with each of the bags having an opening on a side.
Heretofore, continuous bags of thin material have been manufactured by a reel means for supplying a continuous length of advancing thin tubing. The tubing is passed through a perforating blade, perforating said tubing in a plurality of first spaced locations. Sealing means then seal the tubing in a plurality of second spaced locations, thereby forming the continuous bags.
In a co-pending U.S. patent application Ser. No. 230,303 filed by me, I disclosed a method and an apparatus for producing continuous bags of thin material with each of the bags having an opening on a side. In that co-pending patent application, after the continuous bags of thin material separated by a line of perforation is produced, a drag means and a roller means cooperate to cause separation on one side of the bag along the line of perforation. The drag means is located to one side of the bags while the roller means is located to the other side of the continuous bags. The drag and roller means frictionally engage one another to cause the line of perforation on one side of the bags to tear to become a line of separation or an opening to the bags.
In U.S. Pat. No. 2,973,697, a method and an apparatus for producing continuous bags that are notched on one side is taught. The notching of the bags does not result in the production of continuous bags of thin material that are connected along a line of perforation with each of the bags having an opening on the side along the line of perforation.